Electron discharge device



March 27,1945. q R, K LGoRE 2,372,282

ELECTRON DISCHA RGE DEVICE Filed May 28, 1941 l'l l l l I I I ILI I l I I I I I as I INVENT B Gleoryelllf 1:4!

I I I I l l l l lgl l l I I I'I I d8 ATTORNEY Patented Mar. 27, 1945 v 7 uNlTED STATE I PATENT OFFICE ELECTRON momma Device Radio" (lorporatiori 'bf America; a turpentine of Delaware I i Applicationltiayi194l,Seriail l'o;

G'Claiiiis'. (o1. 2504i).

.My invention relates to electron discharge devices, moreparticularly to such devices suitable for use at high frequencies and employing a beam of electrons and deflecting means for said beam to produce a modulated output current. In conventional devices employing a beam and utilizing deflection. means; the electron stream is modulated by deflecting the beam past an aperis inefiicient insofar as the intercepted current which becomes waste current isiconcerned, and; requires the use. of an additional electrode, that is the apertured electrode. This electrode adds ture in an apertured electrode. Such a device electrode capacity ,to the tube, whichat the. higher frequenciesis undesirable since this further affects the efliciency of the tube. as well as increases the number of leakage paths between the various electrode leads. .y

,Hence', it is an object of my invention to provide an electron discharge device particularly useful at high frequencies and employing abeam and deflecting means for the beam for producing. a :modulated output current.

" ,More specifically, it is an object of my-inven tion to provide such anelectron discharge device in. which the transit. time of ,the electrons; the shape and position of the electrodes and the free quencyof the controlling voltage or voltages: are such that the, action ofthe deflection means ,produces a modulated current in the output of the electron discharge device. l The novel features which I believe to be characteristic of my invention are set forth with particularity. in the appended -claims,ybut the inven-'- tion itself will best be; understood by reference to the following descriptiontaken in connectionwith the accompanying drawing in which Figure 1* is adiagram; explaining the theory of operation of an electron discharge device made accordingto my-invention, Figure 2 represents the output current of a device made according to my invention, Figure 3 isa diagrammatic longitudinal section of an electron discharge device andcircuit made ccor om nventio F gur is a modifica tion of the deviceshown in Figure 3 and'its associated circuit an d; Figure 5 shows a tube corree spondingto the tube in Figure {but used in the push-pull output circuit arrangement. 7

Refering to the drawing in Figure 1, the point Q represents an electron source for providing a beam of electronsdirectedbetween a pair of dcfleeting electrodes D1 and D2 Theseelectrons are directed toward anan'odeor output electrode P'h v i' o on im a ire .c en:-. the beam is deflected, the path length of the v intervals. Asa result the electron current reac w 'rea'ches B2. Thus, it is possible by the application o p oper a n olta es and prqper controlling voltage to have all the electrons which, pass through the same plane II T', on the upward swingreach the outputelectrode P at approxtely hesame. estantpiti e.. p

0n the qwnwarsl e eci q qw v h e trons will reach the plate l? at wider and wider ing the output electrode P willhave a wave sha something like that shown in Figure 2. Thus, with a uniform flow of electronsjrom the source Q a modulated current is produced inthe output electrode 1?. ,The screen, 5- is introduced close to. the 1a-te.P.., o t at. th hig req e c 1 duq d. in the .cum le 9d. w l .nbt be reduced appreciablypytransit time effects.

L 'Ihe incorporation or. an electrode structure.

, corr o d n iq th sh ws fi l .1 n

electrondischargedevice. and its associated cir. Qui is s w i f Fi ure ndirectly heated cathode II provides a souroe o f electrons which" is formed into a beam by m eans of the longitudi alm indr ca el tree l xcharm t a exe pe t re. b

canal B precipitant.eet de .11 in ined th es t .t 'iheb ia creene e iroqe ns 19:

v qedin. ront.e....the u r t e ectrode Th c indri l e es res e; s st mcl .mayrsiirrou d. the tput e ectrodeandsg eento: omplete e n nfirm e ril l et t e tsn l;if: so s red-@Input rcu t!! i gqnt q ed .be w the .deflecti'ne electrodes 1 5; nd p. 51 we po nt. on the. re ies urc .21. uput, 2i e nac nnected' etween thetq a e. sou ce 23,... nuimhe .putputl ectr d L, by-nass na of. the. hi h rfrequency curren of t m ine. accomplished by .means of high frequency condenser 23whichalso permits a; different D; C. ,voltage to be applied? to the anode andthe screen. The frequency of the voltage applied to thei'input circuit 20 and bias-' ingvoltages appliedto the'2otherelectrodes' are; such that the velocity of the electrons and the deflection caused by the controlling voltage makes the electron transit time difiercnce between the maximum points of swing equal to one-half the period of the frequency of the applied voltage to the deflecting electrodes I5 and H5, in this way obtaining an output such as shown in Figure 2.

In the modification shown in Figure 4, a special case is shown in which a pair of output electrodes are displaced a distance equal to a multiple of one-half period of the transit time of an electron during half a period. Here again cathode 26 supplies electrons which are formed into a beam by an electrode system which comprises cylinder 21 and apertured electrodes 28 and 29, The beam of electrons passes between deflecting electrodes 38-31 to output electrode elements 32 and 34 screened by means of screen electrodes 33 and 35. Electrode 33 may be on both sides of electrode element 32 to completely shield it from the electron stream when it passes to electrode 34. The input voltage i applied by means of input circuit 36 to the deflecting electrodes 303i, and output circuit 31 is connected to the electrode 34 electrically connected to electrode 32 by means of conductor 39. The spacing between electrodes 32 and 34 is such that the transit time of electrons between the two electrodes 32 and 34 is a multiple of one-half period of the applied controlling voltage. In the case shown the transit time 1- is made equal to one period T. Thus the current pulses reach 32 and 34 in phase. The result of this i a current having twice the amplitude flowing for a half period of the applied input voltage.

In Figure 5 the output electrodes 32 and 34 are connected to opposite sides of a push-pull output transformer. Inasmuch as the transit time space between the two electrodes is made equal to onehalf period, the current flowing to each output electrode is in the proper phase relationship to bring about excitation of the output transformer 31'.

While I have indicated the preferred embodiments of my invention of which I am now aware and have also indicated only one specific application for which my invention may be employed, it will be apparent that my invention i by no means limited to the exact forms illustrated or the use indicated, but that many variations may be made in the particular structure used and the purpose for which it is employed without departing from the scope of my invention as set forth in the appended claims.

' What I claim as new is:

1. An electron device having a cathode for supplying electrons and means for forming said electrons into a directed beam, an output electrode means including a pair of electrode elements positioned at difierent distancesfrom said cathode, deflecting means'between the cathode and output electrode means for directing the beam first on one electrode element and then on the other electrode element, means for applying a controlling alternating input voltage to said deflecting means, and circuit means connected to said output electrode means, the spacing between the electrode elements of the output electrode means being such that the transit time of the electrons between the electrode elements is of the order of a half a period of oscillation of the applied controlling alternating voltage.

2. An electron discharge device having a, cathode for supplying electrons and means for forming said electrons into a directed beam, an outelements positioned at different distances from said cathode, a deflecting means between the cathode and output electrode mean for directing the beam first on one electrode element and then on the other electrode element, means for applying alternating input voltage to said deflecting means, and circuit means connected to said output electrode means, the spacing between the electrode elements of the output electrode means being such that the transit time of the electrons between the electrode elements is of the order of a multiple of half periods of oscillation of the applied controlling alternating voltage.

3. An electron discharge device having a cathode for supplying electrons and means for forming said electrons into a directed beam, an output electrode means including a pair of electrode elements positioned at different distances from said cathode, said electrode element being impervious to electrons, deflectin means between the cathode and output electrode means for directing the beam first on one electrode element and then on the other electrode element, means for applying a controlling alternating input voltage to said deflecting means, and circuit means connected to said output electrode means, the spacing between the electrode elements of the output electrode means being such that the transit time of the electrons between the electrode elements is of the order of multiple or half periods of oscillation of the applied controlling voltage, and screening electrode elements between the deflecting means and said output electrode elements.

4. An electron discharge device having a cathode for supplying electrons and means for forming said electron into a directed beam, an output electrode means including a pair of electrode elements positioned at different distances from 40 said cathode, said electrode elements being image to said deflecting means, the spacing between put electrode means including a pair of electrode the electrode elements of the output electrode mean being such that the transit time of the electrons between the electrode elements is of the order of a half period of oscillation of the applied controlling voltage, and an output circuit connected between the output electrode elements.

5. An electron discharge device having a cathode for supplying electrons and means for forming the electrons from said cathode into a directed beam, an output electrode means comprising a pair of electrode elements at difierent lineal distances from the cathode, and a pair of deflecting electrodes between which said beam is directed to said output electrode means, said beam forming means including an extended tubular conducting member positioned between the cathode and deflecting electrodes and having a transverse member closing the tubular member adjacent the cathode, said transverse member having an aperture registering with the beam of electrons, an input circuit connected to said deflecting electrodes for applying an alternating controlling voltage to said deflecting electrodes, an output circuit connected to said output electrode means, a source of voltage, means connected between said source of voltage and said electron discharge device for providing electrode biasing voltages, the frequency of said alternating controlling voltage being such that the difierence in transit time between the different electrode elements of the output electrode means and the cathode i of the order of a multiple of one-half periods of oscillation of the controlling voltage, and screening electrode elements between the output electrode elements and said deflecting electrodes.

6. An electron discharge device having a cathode for supplying electrons and means for forming the electrons from said cathode into a directed beam, an output electrode positioned to receive the beam of electrons, and a pair of deflecting electrodes between which said beam is directed to said output electrode, said beam form- -ing means including an extended tubular conducting member positioned between the cathode and deflecting electrodes and having a transverse member closing the tubular member adjacent the cathode, said transverse member having an aperture through which the beam of electrons is (ii-- rected, an input circuit connected to said defleeting electrodes for applying an alternatin controlling voltage to said electrodes and output circuit connected to said output electrode, a source of voltage and means connected to said source of voltage and said electron discharge device for providing electrode biasing voltages, said output electrode including a pair of electrode elements positioned at different distances from said cathode, the spacing between the electrode elements of the output electrode means being such that the transit time of the electrons between the electrode elements is of the order of a multiple of half periods of oscillation of the applied controlling voltage.

GEORGE ROSS KILGORE. 

